1. Field of the Invention
This invention relates to a conveyor unloading or discharge mechanism. More particularly, this invention relates to a discharging or stripping mechanism for removing parts, one at a time, from an accumulating type conveyor.
2. Description of the Prior Art
There are many types of conveyor discharge or ejecting systems, and the particular type that is chosen depends on many factors such as the type of conveyor to which the mechanism is applied, and the equipment or location to which the parts are being discharged.
With an accumulating type conveyor, parts are conveyed, usually in a single row by step by step advancement. The parts accumulate or stack up in an abutting relationship at a discharge point or the end of the conveyor. A widely accepted type of accumulating conveyor is known as a lift and carry or walking beam conveyor. One such conveyor of an advanced design is described in U.S. Pat. No. 4,838,411. The conveyor of this patent utilizes a pair of elongated, spaced apart and parallel stationary rails. A pair of movable rails are located between the stationary rails and are capable of moving from a point below the stationary rails to a point above the stationary rails, and from a retracted position to an advanced or forward position. Thus parts resting on the stationary rail, are picked up by the movable rails, and moved forward on the conveyor to a point where they are again lowered to a resting position on the stationary rails. This type of conveyor is particularly advantageously used in conveying not only parts that extend above the rails but also elongate parts which extend between the rails. For example, automotive connecting rods can be conveyed with or without a cap attached to the beam while the beam extends between the rails, or the cap can be conveyed alone supported entirely above the rails.
When the parts are to be removed from the conveyor one at a time, one of simplest type of discharge units employs a staking member which is caused to be inserted between abutting parts in a fashion to push the part at the end of the conveyor to a drop discharge while holding the next part from advancing. This can result in a somewhat harsh and erratic handling of the part which may mark or mar the part by the staking impact or the subsequent guiding contact. This can be entirely unsatisfactory for many parts, particularly in the automotive field as in the foregoing example of conveying and discharging connecting rods.